Wastewater treatment method and apparatus

ABSTRACT

The present invention discloses a method and apparatus for separating particles and dissolved matter from a produced water fluid stream. Specifically, the present invention includes a first pressure source which transports untreated produced water or contaminated aqueous fluid into a separator annulus with a filter element disposed therein. The untreated fluid is placed under appropriate pressure sufficient to produce turbulent flow, increased particle kinetics and/or cavitation allowing the desired fluid to penetrate and pass into and through the, filter media. The treated fluid is then transported to a collection tank. The contaminant matter retained by the filter media may be removed by the nearly instantaneous reverse pressurization of the separator annulus by a second pressure source thereby removing the contaminant particles away from contact with the filter media, and which may then be transported to a waste collection tank or a separator for further treatment.

CROSS REFERENCE TO RELATED DATA

The application is a divisional patent application of Ser. No.12/025,523, filed Feb. 4, 2008 (now U.S. Pat. No. 7,906,023), which is acontinuation-in-part of Ser. No. 11/042,235, filed Jan. 25, 2005 (nowU.S. Pat. No. 7,459,091); which is a continuation-in-part of Ser. No.10/820,538 filed Apr. 8, 2004, (now U.S. Pat. No. 7,291,267); whichclaims the benefit of 60/540,492 filed Jan. 30, 2004.

BACKGROUND OF THE INVENTION

1. Technical Field

The present invention relates to a system for improving the quality ofwaters and fluids produced from petroleum and gas well drilling andrecovery operations, mining operations, and during other industrialactivities, and specifically to a method that does not involve the useof traditional filtration or separation methods. The present systemseparates contaminants from the water and field produced fluidsutilizing a pressure separation apparatus which can also create andfacilitate hydrodynamic cavitation conditions within the produced fluid.This results in the improved separation and removal of particulates anddissolved constituents from the fluid.

2. Description of Related Art

The safe and effective removal of contaminants from water and otherfluids is a consistent problem faced by many industries. The impuritiesaccumulated by water and other fluids during the hydrologic cycle,industrial processes and manufacturing activities may appear in bothsuspended and dissolved forms. Suspended solids may be generallyclassified as particles larger than molecular size (i.e. particle sizesgreater than 10⁻³ mm), which are supported by buoyant and viscous forcesexisting within water. Dissolved materials (i.e. particle sizes lessthan 10⁻³ mm) consist of molecules and ions, which are held by themolecular structure of water.

The presence of suspended and/or dissolved solids in water, wastewaterand other fluids is undesirable for several reasons. The presence ofvisible suspended solids may be aesthetically displeasing. Likewise, thepresence of suspended and/or dissolved solids allows for the adsorptionof other chemicals or biological matter into the fluid. Due to thestandards promulgated by government agencies, excessive contaminantsmust be removed from potable water, wastewater and other types ofcontaminated fluid streams before the effluent may be discharged to theenvironment or recycled for reuse. If establisheddischarge-contamination levels are exceeded, governmental authoritiesand agencies may impose surcharges and penalties on the entityresponsible for the discharge of fluids which does not meet or exceedthe appropriate standard of quality.

Both terrestrial and offshore oil and gas fields produce largequantities of contaminated water that can have significant environmentaleffects if they are not handled, remediated and discharged properly. Ina typical petroleum formation, formation water lies adjacent theformation layer containing the desired hydrocarbons (e.g. oil andnatural gas). As a result, when these hydrocarbons are removed from theformation via the wellbore, formation water is brought to the surfacealong with the hydrocarbons. If required and in order to achieve maximumrecovery, water will be injected into the formation to provideadditional motive force to recover the hydrocarbons from the formation.As a result, increasing volumes of both formation water and injectedwater are produced (also referred to collectively as “produced water”)in the recovery of oil and gas from the formation. The treatment ofproduced water is a major component of the cost of producing oil andgas.

From the present day oil and gas operations occurring around the world,the volume of produced water is certainly not insubstantial. Forexample, 253 million tons of produced water is estimated to have beengenerated from offshore drilling rigs located in the UK sector of theNorth Sea in the year 1998. This produced water was then treatedaccording to processes in place at the time and discharged into theocean. However, the discharged water still contained an average oilconcentration of 22 ppm at the time of discharge into, the ocean.

In typical petroleum recovery operations, produced water is separatedfrom the oil or gas recovered from the formation, treated to remove anyhydrocarbons or other contaminants mixed or dissolved therein, and thendischarged to the surface, ocean, or reinjected into the formation orwell depending on the location of the well. Produced watercharacteristics and physical properties vary considerably depending uponthe geographic location of the field, the geological formation withwhich the produced water has been in contact for thousands for years,and the type of hydrocarbon product being produced. The contaminants ofproduced water include salt content expressed as salinity, conductivity,or total dissolved solids (“TDS”). Other contaminants may includeslurries having dispersed oil droplets, dissolved organic compoundsincluding dissolved oil, drilling fluids, polymers, well treatment andworkover chemicals, and other organic and inorganic compounds that canlead to toxicity. Some of these are naturally occurring in the producedwater while others are related to chemicals that have been added fordrilling and well-control purposes. Further, contaminants can alsoinclude dissolved gases including hydrogen sulfide and carbon dioxide,bacteria and other living organisms, and dispersed solid particles.Produced waters also typically exhibit low concentrations of dissolvedoxygen and non-volatile dissolved organic materials. Because of thecontaminants in produced water, it requires no large amount of thoughtto surmise that the direct release or reinjection of untreated producedwater into the ocean, upon land, or into the subsurface formation wouldhave damaging effects on the environment and pose health risks toanimals and humans in both the short and long term.

Due to the presence of the aforementioned undesiredconstituents/contaminants in produced water, administrative and othergovernmental agencies have enacted legislation which prohibits thedischarge of produced waters containing concentrations of suchcontaminants that are greater than a prescribed concentration level. Forexample, the United States Environmental Protection Agency currentlylimits the content of “oil and grease” in produced waters to 29 ppm(parts per million) with a maximum of 42 ppm. If oil and gas producersdischarge produced waters that contain concentrations of specifiedcontaminants which exceed the specified maximum dischargeconcentrations, severe fines and potential criminal penalties canresult. Therefore, the need for a system which can efficiently andeconomically remove contaminants from produced waters, as dictated bygovernmental statutes and agencies, is of paramount importance toindustry.

One prior art solution for treating produced water involves pumping thewater through disposable filters to filter and remove the suspendedsolids. There are several problems with this prior art solution. First,once the disposable filters have been used they are typically consideredhazardous waste and they must be sent to special disposal facilities fordisposal after use further depleting the increasingly diminishinglandfill space available. Second, the disposable filters are themselvesrelatively costly and therefore do not provide an economical treatmentsolution. Third, the constant changing of used disposable filters withclean or new disposable filters is labor intensive. Fourth, thedisposable filters have a relatively short lifespan as they (1) areconstructed of paper-based material which is easily degraded bycontaminants, (2) are unable to continually support the sheer mass ofthe contaminants that are loaded onto the filters during filtrationoperations, and (3) cannot withstand typical backwash cleaningpressures. Consequently, a need exists for a way to minimize oreliminate the need for disposable filters in the removal of suspendedsolids from waste streams such as produced water.

Another problem encountered in removing contaminants from fluids is theexpense and difficulty in designing a system that can removecontaminants that vary widely in chemical and physical make-up. Asalluded to above, the chemical make-up of contaminants ranges widelyfrom dissolved oil and brine to bacteria in produced waters. Similarlythe physical make-up of the contaminants varies in particle size fromthe ionic range (brine) to the micro and macro particle range (oildroplets). Such a wide range of contaminants presents several challengesin treating produced waters. For example, slurries and biologicalcontaminants can plug filtration equipment, and separation of metalsfrom contaminated water typically requires expensive chemicalprecipitation processes. These are just a sampling of the difficultiesencountered in the treatment of industrial waste water which illustratesthe complexity and expense of treatment facilities that must beconstructed to treat such waste water in lieu of disposable filters.Because such treatment facilities are complex, they are typically notmobile, therefore requiring industrial waste water be stored on-site andthen shipped to a treatment facility. For example, produced water isoften stored in a tank near oil or gas well until the waste can betrucked to a treatment or injection facility. Similarly, treated waterfor recovery operations must be trucked into and stored near thewellhead for petroleum recovery operations such as drilling andfracturing wells. Consequently, a need exists for an improved method andapparatus for treating contaminated water. In one aspect, the apparatusand method should be mobile and able to be economically installed nearthe location where the contaminated water is produced. In one aspect,the apparatus and method should provide sufficient treatment to meetregulatory standards required to permit discharge of Water directly intothe environment. In another aspect, the method and apparatus should beable to provide for the treated water needs of the facility where theapparatus is located. As such, a need exists in the art for a portable,highly efficient filtration apparatus and method which can separatesuspended and dissolved solids and other contaminants in a variety ofenvironments. Further, a need exists for an improved apparatus andmethod of removing particles from fluids in either a liquid or gaseousstate. Further, a need exists for an apparatus and method which canconsistently remove particles of a desired size so as to efficiently andconsistently reduce the chance of the imposition of a surcharge forviolating quality control standards and the release of untreatedeffluents.

SUMMARY OF THE INVENTION

The present invention discloses a method and apparatus for separatingparticles, dissolved matter and chemical sub-fractions from a producedwater fluid stream. In one embodiment, the present invention alsodiscloses a novel separator design which creates or enhances particlekinetics and cavitation physics to increase filtration efficiency andprovides for the separation of chemical sub-fractions from fluid streamsbelow one micron in size. In one aspect, the untreated produced water isplaced under pressure sufficient enhance standard filtration, create orenhance particle kinetic reactions, or to create or enhance hydrodynamiccavitation &ring the separation process wherein suspended and dissolvedcontaminants are separated from the fluid stream within the separator byone or more of said processes during the separation phase. The treatedfluid can then transported to a product collection tank and dischargedor sent to additional treatment or polish mechanisms for furthertreatment. The particulate matter retained by the reusable filter mediais removed by the instantaneous reverse pressurization of the separatorthereby forcing treated waste away from the reusable filter media andinto a reject tank. The waste from the reject tank can then further betreated, optionally, by further dewatering and minimization processes.Any resulting sludge can be further processed as necessary. The driedwaste can then be transported to a waste collection center forappropriate disposal or landfilling. The treated effluent may be safelyused in a variety of ways including being discharged to the environmentfor beneficial reuse (e.g. potable water use or agricultural use),utilized for secondary oil/gas recovery operations or injected intodisposal wells.

Other aspects, embodiments and features of the invention will becomeapparent from the following detailed description of the invention whenconsidered in conjunction with the accompanying drawings. Theaccompanying figures are schematic and are not intended to be drawn toscale. In the figures, each identical or substantially similar componentthat is illustrated in various figures is represented by a singlenumeral or notation. For purposes of clarity, not every component islabeled in every figure. Nor is every component of each embodiment ofthe invention shown where illustration is not necessary to allow thoseof ordinary skill in the art to understand the invention. All patentapplications and patents incorporated herein by reference areincorporated by reference in their entirety. In case of conflict, thepresent specification, including definitions, will control.

BRIEF DESCRIPTION OF THE DRAWINGS

The novel features believed characteristic of the invention are setforth in the appended claims. The invention itself, however, as well asa preferred mode of use, further objectives and advantages thereof, willbest be understood by reference to the following detailed description ofan illustrative embodiment when read in conjunction with theaccompanying drawings, wherein:

FIG. 1 illustrates a process flow diagram for a water treatment systemin accordance with one embodiment of the present invention;

FIG. 2 a is a schematic diagram illustrating the interaction of thefunctional components of the system in which produced water is treatedwith a single flux cartridge unit in accordance with one embodiment ofthe present invention;

FIG. 2 b is a schematic diagram illustrating the interaction of thefunctional components of the system in which produced water is treatedwith a single flux cartridge unit in accordance with an alternativeembodiment of the present invention.

FIG. 3 is a schematic diagram illustrating a cross section of a singleflux cartridge unit according to the present invention;

FIG. 4 provides a more detailed cross-sectional view of the fluxcartridge membrane of a flux cartridge;

FIG. 5 a is a cross-section view of the filter membrane of the fluxcartridge inside the annulus of a separator;

FIGS. 5 b-5 c provide a more detailed prophetic view of the tortuouspath the fluid travels as it is forced through the separation media;

FIG. 5 d is a schematic diagram illustrating a cross section of a singleflux cartridge unit comprising an electrochemical cell according to oneembodiment of the present invention.

FIG. 5 e provides a more detailed cross-sectional view of the fluxcartridge subjected to a magnetic field in accordance with oneembodiment of the present invention.

FIGS. 6A to 6C show the use of multiple stages or, passes of producedwater through the apparatus (or series of apparati) in series, paralleland in combination, respectively;

FIG. 6D shows the use of heat to improve the filtration of contaminantsas it passes through the filtration stages;

FIG. 7 is a schematic of a multi-stage filtration system wherein thereis a first set of apparati in series and then a second set of apparatiin parallel according to one embodiment of the present invention;

FIG. 8A is a table of properties of a field sample of untreated producedwater;

FIG. 8B is a table of properties of a field sample of produced waterafter being treated with a 100 micron flux cartridge according to thepresent invention;

FIG. 8C is a table of properties of a field sample of produced waterafter being treated with a 40 micron flux cartridge according to thepresent invention;

FIG. 8D is a table of properties of a field sample of produced waterafter being treated with a 10 micron flux cartridge according to thepresent invention;

FIG. 8E is a table of properties of a field sample of produced waterafter being treated with a 1.0 micron flux cartridge according to thepresent invention; and

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The present invention is directed towards an improved water treatmentsystem for removing contaminants from water. In one embodiment, the useof hydrodynamic cavitation forces and physics in conjunction withtraditional separation media to treat contaminated water is both noveland a significant improvement over existing traditional filtrationsystems. “Untreated water” is used throughout the detailed descriptionand refers to any water containing one or more contaminants, including,but not limited to “produced water,” “refinery water,” “mining water,”and “pulp/paper wastewater.” As used herein “produced water” is usedinterchangeably with “untreated water.”

As used herein, “contaminant” refers to any physical, chemical,biological, or radiological substance or matter that has an adverseeffect on air, water, or soil and as a consequence of that impact thereis a regulation regarding the discharge of that contaminant into theenvironment.

As used herein, “produced water” means the water or brine brought upfrom the hydrocarbon bearing formation strata during the extraction ofoil and gas, and can include formation water, injection water (including“frac flow back water”), and any chemicals, polymers or drilling fluidsadded downhole or during the oil/water separation process.

As used herein, “mining water” is defined as water used for theextraction and on-site processing of naturally occurring mineralsincluding coal, ores, petroleum, and natural gas. “Mining water”includes water from tailings. Tailings are low grades of mining ore thatare disposed of in mining waste ponds or other fine waste from miningoperations suspended in water.

FIG. 1 illustrates a simplified process flow diagram for a watertreatment system in accordance with one embodiment of the presentinvention. As shown in FIG. 1, untreated water is stored in a tank 10.Depending on the solids content of the untreated water, the untreatedwater can be routed via a pump 20 or other suitable means to acentrifuge 30 to remove heavy constituents, such as sand, dirt, gravel,drilling muds, and other similar material. These heavy constituents canbe routed to a reject tank 60 where it can optionally be dewatered orstored for further processing or disposal 70. In one embodiment, theuntreated water is routed directly to the molecular separator 40 withoutbeing routed to a centrifuge or other similar device.

In one embodiment, additives 12 can be added to the untreated water 10near the pump inlet as shown in FIG. 1 and/or directly to the start tank10. In one embodiment, the additives 10 can be added to help control orremove biological organisms or activity in the untreated water streamthat can promote fouling of the flux cartridge, as discussed in moredetail below. Additives include, but are not limited to sodiumhypochlorite, chlorine(Cl₂), chlorine dioxide (ClO₂), bromine (Br₂),iodine (I), ozone (O₃), bleach, ammonia, metal ions (e.g. Ag⁺ and Cu²⁺),phenols, alcohols and other chemical disinfectant additives as known inthe art. The untreated water from the waste tank can be treated in themolecular separator apparatus 40 to remove contaminants from theuntreated water with the use of reusable filter media. The molecularseparator apparatus 40 also provides the ability to concentratecontaminants and, routes the contaminants to the reject tank 60 androutes treated water or product to a product storage tank 50. In oneembodiment, the treated water from the molecular separator apparatus 40can be further treated by routing the treated water through a disposablenano-filter (not shown) and/or by routing the treated water through areverse osmosis system 52. The operation of one embodiment of themolecular separator apparatus 40 is discussed in more detail below.

FIG. 2 a is a schematic diagram illustrating the interaction of thefunctional components of the system in which produced water is treatedwith a single flux cartridge unit in accordance with one embodiment ofthe present invention. Produced water can be routed from a centrifuge 30as shown in FIG. 1 or it can come directly from a storage tank 401, asdepicted in FIG. 2 a. The produced water may include sulfur compounds,heavy metals, carbonates, brines, salts, drilling fluids, polymers,industrial solvents, or any similar fluid or solid from whichsub-fractions are to be separated.

FIG. 3 is a schematic diagram illustrating a cross section of a singleflux cartridge seated within the annulus of a separator according to thepresent invention. A plurality of these flux cartridges seated withincorresponding annuli may be assembled in parallel and such arrangementmay be referred to as a “Q-pod.” With reference to FIG. 3, a fluxcartridge unit or separator 100 comprises an outer casing 110 forming anannulus region or fluid ring 160 around a single flux cartridge 120. Theouter surface of the flux cartridge 120 is shown. The inside region 130of the flux cartridge 120 is hollow. A sealing ring 140 on the fluxcartridge 120 ensures that no fluid passes between the annulus 160 andthe inside region 130 of the flux cartridge 120 when the flux cartridge120 is sealed in the separator 100.

FIG. 4 provides a more detailed cross-sectional view of the fluxcartridge membrane of a flux cartridge 120 and the filtration ofuntreated fluid as disclosed herein. Produced water is directed into theannulus region 160 and through the flux cartridge 120 under pressure.Fluid enters through an entry port or region 260 under pressure. Due tothe pressure differential between annulus region and the interior region130 of flux cartridge 120, a substantial portion of contaminants areretained on the surface and within the interior fissures of fluxcartridge 120, while the desired fluid effluent is collected in theinterior region 130 of flux cartridge 120 and routed out of the fluxcartridge 120 via fluid outlet 270. In addition, the pressures of thesystem can be manipulated by the user so that the pressure dropexperienced by the fluid moving from the smaller diameter inlet 260 intothe larger volume of the annulus 160 creates the formation of cavitationbubbles resulting in additional filtration and chemical effects asfurther discussed herein.

Referring back to FIG. 2 a, in one embodiment, the filtration processbegins by drawing the produced water from the storage tank 401 by meansof a first pneumatic pump 410. The pneumatic pump 410 alternately drawsthe produced water through two poppet valves 411, 412 via the upward anddownward motion of a plunger 413, and alternately pumps the fluidthrough two outlet lines 414, 415. Although only one flux cartridge unit100 is depicted, each outlet line 414 and 415 can route fluid to aheader in fluid communication with other flux cartridge units 100.Referring back to FIG. 2 a, pressurized untreated fluid is delivered tothe separator via lines 414 and 415. The poppet valves in the valveassembly which is in fluid communication with the separator viatransition plates, controls the movement of untreated fluid into theseparator. As the plunger 413 rises (as shown in the present example),fluid is drawn through a poppet valve 412. Simultaneously fluid ispumped out through the upper outlet line 414. When the plunger 413reverses direction and pushes downward, the lower poppet valve 412closes and the produced water is drawn through the upper poppet valve411 and pumped out through the lower outlet line 415.

The produced water moves through the Outlet lines 414, 415 to aseparator 100 and specifically into the annulus or fluid ring 160. Forthe purposes of FIG. 2 a, a single separator 100 with flux cartridge 120inserted therein is shown for ease of illustration. In one embodiment,the separator contains eight annuli with eight corresponding fluxcartridges seated therein and may be referred to as a Q-Pod. Alternativeconfigurations with additional or fewer annuli and flux cartridges arepossible.

FIG. 2 b is a schematic diagram illustrating the interaction of thefunctional components of the system in which produced water is treatedwith a single flux cartridge unit 100 in accordance with an alternativeembodiment of the present invention: Referring to FIG. 2 b, acentrifugal pump 410 or other suitable pump is used to pump fluid from astorage tank 401 through an outlet line 421 and into a header 422 influid communication with the separator 100. Although only one fluxcartridge unit 100 is depicted, the outlet line 421 can route fluid to aheader 422 in fluid communication with other flux cartridge units 100.

With reference to FIGS. 2 a and 2 b, seated within the separator 100 isa flux cartridge. 120. A flux cartridge 120 comprises a membrane thatassists in the separation of contaminants from the produced water. Aspace (referred to herein as a fluid ring 160) exists between the insidesurface of the separator 100 and the outer surface of the flux cartridge120. As produced water is delivered to the separator with the first pumpoutlet line 414, it passes through a poppet valve 424 and into the fluidring 160. When the produced water is delivered with the second or lowerpump outlet line 415, a corresponding poppet valve 424 closes and thefluid passes through a second poppet valve 423 and into the fluid ring160.

Referring to FIGS. 2 a, 2 b, and 4, once in the fluid ring 160, theproduced water moves in a turbulent manner whereby contaminants areremoved via pressure filtration, particle kinetics and hydrodynamiccavitation as discussed in greater detail herein. Fluid passes into andthrough the flux cartridge membrane and into the interior chamber 130 ofthe flux cartridge 120. Contaminant particles and larger molecules 210are left behind as residue in the fluid ring 160, and on the exteriorand within the fissures of the flux cartridge 120. The pressure suppliedby the first pump 410 pushes the treated product out of the center ofthe flux cartridge 120 through a flux cartridge exit valve 427 and intoa second pump, called a pneumatic ejector pump 430. Alternatively, thetreated fluid product may leave the flux cartridge 120 through anejector bypass valve 428 and travel directly to a product collectiontank 402. This ejector bypass is used when a single ejector pump 430services multiple separator filter pods in alternative embodiments ofthe present invention.

During the filtration cycle described above, the ejector pump plunger431 is drawn up (as shown in FIGS. 2 a and 2 b) into a charged “ready”state. Next, check valves 432, 433 that are built into the plunger'sdisc, are opened. In this position, the check valves 432, 433 allow thetreated product coming from the flux cartridge 120 to pass by theplunger 431 and out of the ejector pump 430 and into the productcollection tank 402. This filtration cycle repeats for each annulus/fluxcartridge within the separator pod for a pre-determined time period(e.g., 20-25 seconds) or until separation efficiency declines below apre-determined level. At the end of this separation cycle period, theeach annulus/flux cartridge within the separator is backwashed andcleaned with a reverse flush (ejection cycle). The annuli/fluxcartridges can be backwashed all at once, or programmed to backwash atindividually at the desired interval, thereby allowing the system tomaintain continual filtration, while backwashing at the same time.Alternatively, a sensor assembly may be employed to measure the pressuredrop across the flux cartridge or other appropriate location. When thepressure differential becomes excessive, or reaches a certain value, thesensor assembly sends a corresponding signal to the central controllerwhich initiates reverse flush operations (ejection cycle). Such sensorassemblies are known in the art and further description thereof isconsidered unnecessary.

Referring to FIG. 2 a, the reverse flush operation or ejection cyclebegins by stopping the first pump 410 and shutting the poppet valves423, 424 at the top of the separator 100 of the separator filter pod. Inthe embodiment using the centrifugal pump 420 depicted in FIG. 2 b, thepump 420 is not shut off as it is still serving other separators (notshown) when one of the separators is in the backwash cycle. Next, thepneumatic ejector 430 is activated and its plunger 431 is drivendownward. This motion closes the plunger's check valves 432, 433 andstops the flow of treated fluid past the plunger 431, allowing theplunger to exert pressure on the fluid inside the ejector. The fluid ispushed back through the flux cartridge exit valve 427, through the fluxcartridge 120 and into the fluid ring 160. The time period for thisreverse ejection flush or ejection cycle is approximately 0.35 secondsand is carried out under higher pressure than the normal filtrationcycle driven by pump 410. For example, the pressure exerted on theproduced water by the first pump 410 may be up to 150 psi (1.03 MPa)depending on the viscosity of the fluid involved. In contrast, thepressure exerted by the ejector 430 during the reverse flush may be upto 300 psi (2.06 MPa). This quick, high-pressure reverse burst removescontaminant particles and residue remaining within the fissures andoutside surface of the flux cartridge 120 and re-homogenizes theparticles and residue in the fluid ring 160.

In the next phase of a typical cycle, a poppet valve 426 on the bottomof the separator 100 is then opened to allow the pressurized contaminantparticles and residue solution to flush out of the fluid ring 160 andinto a concentrator annulus 442 or directly to a reject collection tank403. The concentrator annulus 442, as its name suggests, concentratesthe material flushed from the separator 100 by removing a significantportion of the flush fluid used during the ejection cycle. Unlike theseparator filter pod, which may contain up to eight annuli in thepreferred embodiment, the concentrator 440 contains only one annuluswith a flux cartridge 441 seated therein in a preferred embodiment. Theflushed contaminant waste enters the concentrator annulus 442 through anopen poppet valve 443 and into the interior chamber of theconcentrator's flux cartridge 441. The desired effluent fluid passesthrough the membrane of the flux cartridge 441 and into the fluid ring442, leaving the concentrated contaminant waste residue in the interiorchamber of the flux cartridge 441. A fluid return poppet valve 447 inconnection with the bottom or one end of the separator annulus 442allows the treated fluid in the fluid ring 442 to return to the startingtank 401. Next, the poppet valve 443 through which the waste fluidentered the separator 440 is closed and a drying air poppet valve 444 isopened to let drying air into the interior chamber of the separator fluxcartridge 441. This drying air provides a mechanism to dewater theconcentrated waste and drives additional flush fluid through the fluxcartridge 441 membrane and through the return poppet valve 447.

The drying air poppet valve 444 and fluid return poppet valve 447 arethen closed, and a purge air poppet valve 445 is opened to allow inpressurized purging air into separator 440. When the air pressure insidethe separator 440 reaches a pre-determined or desired level (e.g. 110psi), poppet valve 446 is opened which allows the waste residue insidethe flux cartridge 441 to escape into a waste collection tank 403. Inalternative embodiments, a settling tank may be used in place of theseparator 440 to permit produced water to be recycled back into the tank401 or to produce a final product.

Referring now to FIG. 5 a, a portion 503 of a single flux cartridge 120as shown in FIGS. 2-4 illustrates filtration in more detail according toone embodiment of the present invention. The flux cartridge comprisesthe membrane that filters the contaminants from the produced water 501,160. In one embodiment, the porous matrix of the filter membrane 503 iscreated by pressing or sintering metal powder, metal fibers, woven metalmesh, or any combination of these materials, at high pressure and thenannealing it using well-known metallurgical techniques known in themetallurgical art.

This type of filter membrane provides filtration at both its surface andin its depth. Specifically, although the pores at the surface of thefilter membrane 503 may be larger than the filter specification, theflow path through the filter is tortuous and contaminant particles areintercepted by the metal media. Sintered metal media typically exhibit ahigh porosity, and therefore high flow rate and low pressure drop, withexcellent contaminant particle retention. In one embodiment, the presentinvention uses a lower membrane thickness than those typically found inthe prior art (e.g. 0.125 inches (3.2 mm) instead of a prior artmembrane thickness of about 0.40 inches (10 mm)). A thinner filtermembrane 503 produces a much higher flow rate of fluid through thefilter membrane. Lower thicknesses are possible, in part, because ofcontrolled fluid turbulence which is present in the fluid ring 160during operation Of the invention disclosed herein. In the disclosedembodiment, the preferred fluid ring length (l) is 0.125 inches (3.2 mm)when used in conjunction with a flux cartridge diameter of 0.375 inches(9.5 mm). These dimensions have been found to optimize the volume ofreverse flush fluid required to clean the separator annuli and tominimize the amount of reverse flush fluid required to clean theseparator annuli. To obtain effective filtration and reverse flushefficiencies utilizing the apparatus embodiment described herein, thedesired ratio of fluid ring length (l) to the diameter of flux cartridgeutilized is typically 1 to 3, when using a 0.375 inch (9.5 mm) diameterflux cartridge.

The turbulent flow of the produced water in the fluid ring 160 isrepresented by a curved arrow 510. This turbulent flow is created andcontrolled by the pressure differential and the rhythmic pumping actionof the pneumatic pump (pump 410 in FIG. 2 a) and actuation of the poppetvalves within the valve head assemblies of the separator. As the outletstream poppet valves (i.e. 423, 424 in FIG. 2 a) of the first pneumaticpump open and close with the pumping action, a temporary drop inpressure in the fluid ring 160 is caused when the poppet valves switchposition (open or closed), creating a sudden velocity differential andcorresponding pressure drop in the fluid ring. This effect is magnifiedby the suction and pulsing action after each infusion of fluid as thepoppet valves open and close. As a result, fluid pulses up and downwithin the fluid ring 160 resulting in the turbulence represented by thearrows 510 in FIG. 5 a. This turbulence is again magnified by the highvelocity of the fluid moving through the relatively small volumetricspace in the fluid ring.

Laminar flow consists of fluid flowing in straight lines at a constantvelocity. If the fluid hits a smooth surface, a circle of laminar flowresults until the flow slows and becomes turbulent. At fastervelocities, the inertia of the fluid overcomes fluid frictional forcesand turbulent flow results producing eddies and whorls (vortices). Thepresent invention uses turbulent fluid flow for improved molecular andparticle kinetics such that only the desired, smaller molecules 530(e.g. water) pass through the membrane matrix 503. In one embodiment, topass through the fissures of the flux cartridge membrane 503, a moleculein the fluid ring 160 has to enter interstices or fissures at almost a90 degree angle or perpendicularly to the surface of the membrane 503when the molecule enters the membrane (as represented by the arrow at aright angle 520). Due to the constant fluid turbulence, only the lightermolecules are able to make this turn quickly enough to pass through themembrane 503 and enter the interior chamber of the flux cartridge. Heavymolecular contaminants (e.g., suspended solids, iron complexes, oil andgrease) cannot turn fast enough to reach the appropriate entry vector orangle when they contact the membrane 503. As shown in FIG. 5 a, whenheavier molecules hit the uneven surface of the membrane surface, ratherthan pass through, they careen off and strike similarly sized molecules,causing them in turn to scatter and thereby increase the kinetic energypresent in the fluid ring between the annulus and flux cartridge. Thiskinetic pattern is illustrated by arrow 540. In the absence of fluidturbulence or when laminar fluid flow conditions exist, the heaviermolecules in the fluid would lose a majority of their kinetic energy andwould not be able to enter the membrane. Thus, fluid turbulence isnecessary to keep the heavier molecules bouncing off the surface ofmembrane 503. As fluid turbulence increases, the smaller a molecule hasto be in order to be properly oriented to pass through the membrane 503.Therefore, the filtration of smaller molecules can be accomplished byusing a flux cartridge with a less porous membrane matrix, by increasingthe fluid turbulence within the separator fluid ring 160, or by acombination of the two. Consequently, the present application canprovide an effective means of separating total suspended solids (TSS)from untreated fluids with the use of a reusable filter.

The present invention also provides a novel method of achieving thefiltration by membrane emulation, since the filtering effects of asmaller membrane matrix can be achieved without actually changing theporosity of the flux cartridge interstices. Referring back to FIG. 2 a,a slipstream poppet valve 425 controls the flow of fluid from theseparator fluid ring 160 to a slipstream fluid hose or path 404 thatfeeds back to the start tank 401. During membrane emulation, thisslipstream poppet valve 425 is opened while the first pneumatic pump 410is pumping pressurized produced water into the separator fluid ring 160,which allows the produced water to move through the fluid ring 160 at afaster velocity due to the increased pressure differential. When thepoppet valve 425 is opened, flow in the fluid ring 160 is substantiallyvertical. Because the friction forces imparted by the inner and outercircumference of the fluid ring 160, the velocity profile is parabolicmeaning that fluid travels faster as distance from the either the inneror outer circumference increases. Consequently, particles willagglomerate on the surface of the flux cartridge 120 thereby decreasingthe effective pore size of the flux cartridge. In effect, this reducesthe size of particles which are able to pass through the reduced porespace of the flux cartridge 120. As a result, the ability to create thiscondition on the flux cartridge allows the operator to “emulate” afilter porosity with is smaller than the physically measured porosity ofthe flux cartridge 120. With this membrane emulation technique, thepresent invention is able to turn, for example, a five micron fluxcartridge into the functional equivalent of a one micron flux cartridgeby manipulating the pressure and flow conditions existing in theseparator fluid ring 160 due to the large pressure differential createdby the slipstream path 404.

The present invention also provides a way to remove, dissolved materialssuch as brine from untreated water. For example, returning to FIG. 5 a,another effect produced by the filter matrix 503 is cavitation of thetreated fluid as it passes through the membrane 503. Cavitation isdefined as the formation, expansion, and implosion of microscopic gasbubbles in liquid. Cavitation is produced when the static pressure in afluid falls below its temperature-related vapor pressure. A forcefulcondensation or implosion of the bubbles occurs when the fluid reaches aregion of higher pressure.

Without being bound by theory, it is believed that the turbulent forcescaused by the filtration and ejection cycle of the present inventioncreates pulsating energy waves that causes hydrodynamic cavitation andresults in both physical and chemical changes to contaminants such asdissolved solids, hydrocarbons and more complex chemical structures. Itis also believed that cavitation bubbles having localized areas of verylocalized, extremely high temperatures (perhaps greater than 5000 K)(“hot spots”) and pressures (perhaps greater than 1000 atm) are createdwithin the bubbles during the collapse of microscopic vacuoles orbubbles thereby causing several physical and chemical phenomenaincluding, but not limited to, flocculation and oxidation reactions.Under these extreme conditions, it is believed that organic compoundsare decomposed due to the collapse of these bubbles described below.Other compounds or species present in the surrounding condensed layeralso undergo reactions comparable to those found in high temperaturecombustion. It is also believed that cavitation reactions may result inthe creation of free radicals which in turn promote oxidation reactionsthat decompose organic species in the produced water. For example,cavitation of water can cause dissociation of water into hydrogen andhydroxide. The free hydroxyl radical OH is a powerful oxidizing agentand can facilitate removal of dissolved organic material from thetreated fluid. Oxidation caused by hydrodynamically inducing cavitationis known to be orders of magnitude stronger than oxidation caused by theultrasonic induction of acoustic cavitation (discussed below).

It is also believed under such hot-spot model that the maximumtemperature realized in a collapsing bubble decreases as the thermalconductivity of the dissolved or entrapped gases increase. Becausehigher hot spot temperatures are believed to be more advantageous forthe degradation of some contaminants, in one embodiment, the thermalconductivity of the dissolved gases in the fluid ring 160 is physicallyor chemically lowered. For example, to physically lower the thermalconductivity, in one embodiment, air or other gas is cooled prior tobeing supplied to the fluid ring 160. In one embodiment, the separator100 unit is cooled by any suitable method known in the art.

There are generally three regions where chemical and physical phenomenaoccur in cavitation: (1) the gas phase within the cavitation bubblewhere elevated temperature and high pressure are produced, (2) theinterfacial zone between the bubble and the produced water or solutionwhere the temperature is lower than inside the bubble but still highenough for certain reactions to occur, and (3) the fluid of the producedwater at ambient temperature wherein reactions and diffusion are takingplace.

FIGS. 5 b-5 c provide a more detailed prophetic view of the tortuouspath the fluid travels as it is forced through the separation media, inaccordance with one embodiment of the present invention. As discussedabove, cavitation is defined as the formation, expansion, and implosionof microscopic gas bubbles 554 in liquid. The shockwaves produced by thecavitation may accelerate particles 556 to high velocities and increaseinter-particle collisions. Additionally, localized spots of hightemperature and high pressure may be produced during the final phase ofimplosion. The presence of these localized high temperature and highpressure gradients in addition to the kinetic energy formed by theshockwaves may encourage the decomposition of larger molecules by bothmechanical and thermal means. For example, the mechanical energyimparted on large molecules, such as oil, grease or polymers in thefilter media may be analogous to pushing, extruding, or forcing a largecircular molecule through a smaller pipe and may force theintra-molecular bonds to be overcome. The cavitation may occur in theinner fissures or interstices of the flux membrane and/or the interiorof the flux cartridge in the vicinity of the flux cartridge membraneduring the filtration cycle or in the vicinity of the fluid ring duringthe ejection cycle.

Referring back to FIG. 5 a, as the treated fluid passes through theinterstices of membrane 503 cavitation results and gas bubbles areproduced. When these gas bubbles reach the inner fissures of the fluxcartridge and membrane 503 (e.g. arrow 530) they begin to rapidlyimplode. During this implosion process, similar and dissimilar moleculesflocculate and form precipitates. Molecular bonds are broken and freeradicals are created further enhancing the filtration process. Anothereffect produced by the separation media is the breakup of emulsions inthe treated fluid. As the filter fluid is pushed through the separationmedia or flux cartridge membrane 503 under pressure, and as cavitationreactions occur, emulsions in the fluid are broken. By using differentsize filter matrices and fluid velocities, the present invention iscapable of separating particles 300 microns in size and smaller. Thedifferent filter sizes provide a variety of conditions that causedesired amounts and rates of cavitation.

With reference to FIG. 5 a, sediment in the produced water can buildupalong the outer perimeter of the flux cartridge 120 in the fluid ring160. Such build-up is especially likely to occur at the first filter podor when there is a step change to a filter pod having a flux cartridgemembrane with a smaller micron filter matrix. As a result, the firstfilter pod to process produced water or the first filter pod where thereis a step change in the micron size of the filter matrix, may functionmore as a traditional pressure filter by mostly removing total suspendedsolids than a cavitation device. Such build-up material can bebackflushed by a pressure exerted, for example, by a first pneumaticejector 430 (shown in FIG. 2 a) through the flux cartridge 120 and intothe fluid ring 160.

The separation apparatus and method disclosed herein can be enhancedwith the addition of various other separation methods to the separatoras discussed in detail below.

Biocide

In one embodiment, the filter membrane 503 comprises a ceramic fluxcartridge. Ceramic flux cartridges are known in the art and areavailable from vendors such as Doulton USA of Southfield, Mich., USA. Inone embodiment, filter membrane 503 acts as a biocide to destroybiological material in the untreated water. In one embodiment, the fluxcartridge is impregnated with a biocide. In one embodiment, the filtermembrane 503 further comprises a colloidal silver-impregnated ceramicfilter. Such impregnated filters are known in the art as illustrated byU.S. Published Patent Application No. 2007/0110824, which is herebyincorporated by reference. Other methods of manufacturing filtermembranes 503 will be apparent to those of skill in the art.

Electrochemical Cell

FIG. 5 d is a schematic diagram illustrating a cross section of a singleflux cartridge unit comprising an electrochemical cell according to oneembodiment of the present invention. In one embodiment, the fluxcartridge 100 comprises two or more electrodes and an electrical currentsource. As shown in FIG. 5 d, in one embodiment, the flux cartridge 100comprises two cathodes 170, one anode 180 between the two cathodes, andan electrical current source 190. Such cells are known in the art asexemplified by WO 99/16715 and U.S. Pat. No. 4,384,943, both of whichare hereby incorporated by reference in their entirety. In oneembodiment, the electrodes 170,180 are circumferential plates and can beperforated to facilitate the flow of fluid within the fluid ring 160. Asshown in FIG. 5 d, a cathode 170 is on each longitudinal side of theanode 180. However, such embodiment is provided for purposes ofillustration and not limitation and any suitable arrangement can beused. In an embodiment not shown, the casing 110 itself can be anelectrode. In one embodiment, the anode 180 can be made of titaniumcoated with a catalytic coating or can be made of another suitablemetal. In one embodiment, the cathode 170 can be made of steel. In oneembodiment, the electrochemical cell is used to precipitate out metalsand dissolved constituents in the fluid in the fluid ring during theseparation cycle which are then removed via the backwash ejection cycledescribed herein. Likewise, if sufficient current is used, theelectrochemical cell is used to destroy biological material within thefluid ring 160.

Electromagnetic Field

FIG. 5 e provides a more detailed cross-sectional view of the fluxcartridge subjected to a magnetic field in accordance with oneembodiment of the present invention. In one embodiment, the untreatedfluid is subjected to a magnetic force, magnetic field or magneticgradient upon entry into the fluid ring of a separator to collect oragglomerate solid particles affected by Such magnetic field. Suchfiltration methods are known in the art as disclosed in U.S. PatentPublication No. 20060191834, which is hereby incorporated by referencein its entirety. The magnetic force can significantly affect particlemovement during the filtration process, in some cases contributing tothe formation of a filter cake on the surface of the flux cartridge (notshown) and/or on the inner surface of the outer casing 110, as depictedin FIG. 5 e. When the particles agglomerate into larger molecules 210,there is an increase in their effective diameter in turn increasing thefiltration efficiency of the flux cartridge unit. The magnetic field canbe applied at any angle to the direction of pressure driving theuntreated fluid through the flux cartridge, whatever proves mosteffective for the fluid undergoing filtration. The field can be appliedparallel, perpendicular, or at any angle in relation to the direction offluid flow. The means for subjecting a magnetic field or gradient to theuntreated fluid may include a solenoid attached to or contained withinthe filter pod or flux cartridge or a permanent magnet internal orexternal to the filter pod and/or flux cartridge. Typical ranges ofhomogenous magnetic field strengths which would be useful in thisapplication are greater than 0.01 T.

In one embodiment, the flux cartridge 100 is subjected to a magneticfield such that when fluids having magnetic materials such as ironfilings, enter the annulus, the magnetic field can be activated so thatthe magnetic materials are moved outwardly in the direction shown by thearrows. Consequently, the magnetic materials are attracted toward andretained on the outer casing 110 in the fluid ring 160. Then, just priorto or immediately after the backwash operation is initiated, the fieldcan be released and the retained magnetic materials are flushed out ofthe annulus during the backwash ejection cycle.

Acoustic Cavitation Via Ultrasound

In one embodiment, the hydrodynamic cavitation caused by themanipulation of pressures within the separator and filter medium iscoupled with acoustic cavitation to further enhance the overallcavitation reaction that occurs in the molecular separator. In oneembodiment, an ultrasonic wave source is coupled to the flux cartridge100 to create acoustic cavitation. As used herein, “acoustic cavitation”is defined ultrasonically-induced cavitation. Stated differently,“acoustic cavitation” is the formation, growth, and collapse of bubblesoccurring as from an ultrasound source. Ultrasonically-inducedcavitation can be provided by an ultrasound probe inserted into thefluid ring of the flux cartridge 120. In one embodiment, the filtermembrane 503 comprises one or more ultrasonic probes to facilitateacoustic cavitation.

There are two types of acoustic cavitation—stable and transient.Transient cavitation occurs at greater acoustic pressures, where bubblesviolently implode after a few cycles. This implosion can have a numberof effects, including transiently raising the local temperature byhundreds of degrees Celsius and the local pressure by hundreds ofatmospheres, emitting light by a poorly-understood phenomenon calledsonoluminescence, creating short-lived free radicals, which in turnpromote oxidation reactions that decompose organic species in theproduced water. Acoustic cavitation can effect a number of acousticchemical and biological changes in a liquid. Consequently, in oneembodiment, transient acoustic cavitation is used to destroy thebiological material in untreated water. Transient acoustic cavitationcan occur at frequencies between about 20 and about 350 kHz.

Stable acoustic cavitation can occur at low-pressure portions of anultrasound wave and can occur at frequencies between about 700 and 1000kHz. Because stable acoustic cavitation bubbles have less time to grow,they are smaller and therefore result in a less vigorous implosions andcollapse than occurs in transient acoustic cavitation.

Example of Produced Water Treatment Array

FIG. 6A is a schematic diagram of one embodiment of the presentinvention depicting multiple treatment stages in series. With referenceto FIG. 6A, untreated or produced water is passed in series throughmultiple separator filter pods or stages. Impurities are concentratedand collected from one or more stages into a separate receptacle.Treated water is collected at the end of the stages in series. Stagescan be added as desired to further filter impurities from producedwater. Each stage may contain a flux cartridge having the same porosity(e.g. five microns). Alternatively, successive stages may havesuccessively smaller or successively larger porosities. Further,successive stages may have an apparent random variation of porositieswhich are selected by experimentation so as to effect a desiredseparation or filtration depending on the chemical and physical makeupof the produced water. For example, a first stage may use 100 micronflux cartridges while a second stage may use five micron fluxcartridges. Any number of successive stages in series may be used untildesired water purity is obtained. A reverse osmosis system can then beused to remove any remaining dissolved solids in the water.

FIG. 6B is a schematic diagram of another embodiment of the presentinvention depicting multiple stages in series and in parallel. Withreference to FIG. 6B, the capacity to filter contaminated water can beincreased by adding stages in parallel. Also, the degree of filtrationand resultant treated water can be similarly controlled by adding stagesas desired in series. A reverse osmosis system can then be used toremove any remaining dissolved solids in the water. In one embodiment,the treated water in FIG. 6 a or the filtered water in FIG. 6 b can befurther treated with a hydrocarbon removal media such as activatedcarbon and/or other suitable material such as is available from MycelxTechnologies Corporation of Gainesville, Ga., USA.

FIG. 6C is a schematic diagram of one embodiment of the presentinvention depicting multiple first stages in parallel and the remainingstages in series. With reference to FIG. 6C, untreated or produced wateris fed into multiple filter pods at stage one before being combined andsent through a single pod for each of the remaining stages. The treatedproduct is collected at the end of the process. The concentratedimpurities are taken from stage one and from each of the stages. Anynumber of pods or stages, such as the arrangement shown in FIG. 6C, maybe assembled into a unified functioning apparatus.

The embodiment shown in FIG. 6C is especially advantageous if there arelarge amounts of relatively large suspended solid impurities in theproduced water which clog the pores of the first set of flux cartridges.The impurities are drawn off at the first stage by ejection cycles.Further, it may be desirable to operate the filtration and ejectioncycles at a much greater frequency in the earlier stages to furtherensure that particles and impurities do not excessively become bound inthe pores of the flux cartridges. The filtration and ejection cycles ateach stage may be performed at any rate at any given stage whether thestages are in parallel or in series.

FIG. 6D is a schematic diagram depicting a series of filter stageshaving decreasing filter membrane sizes and a heat source. Withreference to FIG. 6D, filtration of produced water is improved by theuse of heat to lower the viscosity of the aqueous solution. The lowerviscosity improves the flow of fluid through the filter membranes, andespecially through the smaller porosity filter membranes. Lowering theviscosity also lowers the resistivity of the fluid and permits suspendedcontaminants to settle out of solution where they can be more easilybackflushed during an ejection cycle into a settling tank (not shown).

It should be further noted that the various streams and/or fluxcartridge can also be cooled to cause contaminants such polymers orflocking agents (common constituents in drilling fluids) in theuntreated water to become brittle and/or precipitate out of solution inthe fluid ring. Consequently, in one embodiment, one or more of the fluxcartridges comprising the first stage are cooled to precipitate outcontaminants in the fluid ring. In one embodiment, the untreated fluidis cooled prior to entering the fluid ring to precipitate out componentsprior to entering the first separator.

Ultraviolet Disinfection

It should be further noted that other treatment technologies besidesheat can also be applied in unit operations placed in before, between orafter molecular separators as depicted by the heat source in FIG. 6 d.For example, in one embodiment, ultraviolet radiation (UV) is used tobreak down organic contaminants and inhibit bacterial growth. UVdisinfection transfers electromagnetic energy from a mercury arc lamp toan organism's genetic material (DNA and RNA). When UV radiationpenetrates the cell wall of an organism, it destroys the cell's abilityto reproduce. UV radiation, generated by an electrical discharge throughmercury vapor, penetrates the genetic material of microorganisms andretards their ability to reproduce. The effectiveness of a UVdisinfection system depends on the characteristics of the wastewater,the amount of time the organisms are exposed to the UV radiation, andthe reactor configuration.

The optimum wavelength to inactivate organisms is in the range of 250 to270 nm. Low pressure lamps emit essentially monochromatic light at thewavelength of 253.7 nm. Standard lengths of low pressure lamps are 0.75m to 1.5 m with diameters of 1.5 cm to 2.0 cm. Generally, two types ofUV reactor configurations exist: contact types and noncontact types. Inboth configurations, the fluid to be treated can flow parallel orperpendicular to the lamps. In the contact reactor, a series of mercurylamps are enclosed in quartz sleeves over which the fluid to bedisinfected is routed. As the fluid passes over the lamps, UV radiationpenetrates the cells of organisms suspended in the fluid and effectively“kills” the organism. In a noncontact reactor configuration, UV lampsare suspended outside a transparent fluid conduit, which carries thefluid to be disinfected. In both types of reactors, a ballast or controlbox, provides a starting voltage for the lamps and maintains acontinuous current.

The advantages of UV disinfection include: (1) effective inactivation ofmost spores, viruses, and cysts, (2) UV disinfection leaves no residualeffect that can be harmful to humans or aquatic life, and (3) UVdisinfection has a shorter contact time when compared with other formsof disinfection (approximately 20 to 30 seconds with low-pressurelamps).

FIG. 7 is a schematic diagram of a series of four filter separatorannuli 701, 702, 703, 704 each having a flux cartridge 710 in accordancewith one embodiment of the present invention and illustrating theprinciple shown in FIG. 7. As in FIG. 2 a, the annuli in FIG. 5 are forillustrative convenience and represent one or more annuli in a filterpod. Similarly, although a single series of separator annuli isillustrated in FIG. 7, several such parallel operations may worktogether to increase production volume as shown by the portion of FIG. 7titled “optional parallel operation.”

With reference to FIG. 7, produced or production water 760 is routed bya pump (P) 750 to a first filter annulus 701 and flux cartridge 710having an effective porosity of 100 microns. A fluid ring 720 existsbetween the inside surface of each annuli 701, 702, 703, 704 and theouter surface of its corresponding flux cartridge 710. The effluent 711from the first flux cartridge 710 passes into a second filter annulus702 wherein it is further treated with a second flux cartridge 710having an effective porosity of 40 microns. A second pump 750 passes thetreated effluent from the second annulus 702 into the third annulus 703wherein the fluid is treated a third time through a flux cartridge 710having an effective porosity of 10 microns. Finally, the treatedeffluent from the third annulus 703 is passed into the fourth annulus704 wherein its flux cartridge has an effective porosity of one micron.

In the embodiment shown, the pumps (P) 750 and ejectors (E) 751, 752pneumatically operate at different time intervals that cycle between afiltration cycle (when the pumps P are operating) and an ejection cycle(when the ejectors E are operating). For example, the filtration cyclecan occur for a pre-determined amount of time and at the end of thispre-determined amount of time, each separator unit or Q-pod can bebackwashed with a reverse flush from the ejector E as explained inregard to FIG. 2 a. In alternative embodiments, variables with orwithout time can be used to determine the length of each cycle interval.One such variable may be an average pressure differential that developsacross the flux cartridges 710 of each Q-pod. In one embodiment, thefiltration cycle causes an average pressure drop across the fluxcartridge membrane of between about 30 and 50 psi (0.2 and 0.35 MPa) andthe ejection cycle causes an average pressure drop across the fluxcartridge of between about 100 and 300 psi (0.7 and 2.0 MPa). Vigorousbackwash forces refresh each flux cartridge and help maintain theturbulent fluid dynamics occurring within the fluid ring of each filterunit. The filtration cycles and ejection cycles can be optimized basedupon the amounts and types of contaminants in the produced water.

FIGS. 8A-8E are tables of measured properties of actual fluid streams asthey are processed or treated through four stages or “passes” of oneembodiment of the present invention. Four Q-pods are used in parallel ateach stage. A pump forces the effluent from each stage to the nextsuccessive stage. The pressure measurements recorded for these pods aretaken during all phases of the filtration process. During a filteringcycle, the inside Q-pod pressure is normally less than the outside Q-podpressure indicating a pressure drop across the filter membrane or fluxcartridge. In FIGS. 8B-8E, the inside pressure of a particular Q-pod maybe the same or more than its corresponding outside pressure. In thiscase, the particular Q-pod may be in a backwash cycle. During afiltering cycle, the inside Q-pod pressure may be less than the outsideQ-pod pressure.

FIG. 8A illustrates the properties of a sample of produced water beforebeing treated. The untreated sample has a nephelometric turbiditymeasurement is 3 NTU. Its total dissolved solids (TDS) measurement is9.02 ppt or parts per thousand. Its pH is 8.72, its temperature is 32deg. C., and its conductivity is 17.91 mS or milli-siemens. Its specificgravity is 1.008 and its chloride concentration or “chlorides” is 15,180ppm or parts per million.

FIG. 8B illustrates these same properties for the two fractions exitingfrom the first parallel set of four pods. These pods each have a 100micron flux cartridge and together have treated 70 gallons of theproduced water or “start sample” of FIG. 7A. The values for the productor treated stream are about the same as for the start sample except thatthe conductivity has risen to 18.29 mS and the chlorides have dropped to12,375 ppm. On the other hand, the values for the reject stream reflectsome increased concentration of contaminants. Specifically, the rejectstream turbidity has risen to 15 NTU. However, the chlorides have alsobeen reduced from 15,180 to 13,200 ppm. This phenomenon is at leastpartly due to the induced chemical reactions from the fluid turbulenceand hydrodynamic cavitation occurring in each pod.

FIG. 8C illustrates the same properties for the two fractions exitingfrom the second parallel set of four pods. These pods each have a 40micron flux cartridge and together have treated 70 gallons of thetreated or product stream from the first pass or stage shown in FIG. 7B.The TDS for both product and reject streams has dropped to 8.29 and 8.23ppt, respectively. The conductivity for both product and reject streamshas dropped to 16.38 and 16.50 mS, respectively. Similarly, thechlorides for both product and reject streams has dropped to 8,413 and8,520 ppm, respectively. After two stages, the product stream turbidityhas remained at or near 3 NTU while the reject stream has beenconcentrated to 16 NTU.

FIG. 8D illustrates the same properties for the two fractions (productand reject) exiting from the third parallel set of pods. These four podseach have a 10 micron flux cartridge and have treated the product streamas shown in FIG. 7C. The TDS for both product and reject streams hasremained relatively constant at 8.41 and 8.43 ppt, respectively. Theconductivity likewise has remained relatively constant at 16.89 and16.83 mS, respectively. Remarkably, after three stages, the productstream turbidity has remained at or near 3 NTU while the reject streamturbidity has been further concentrated to 32 NTU.

FIG. 8E illustrates the same properties for the two fractions (productand reject) exiting from the fourth and final parallel set of pods.These four pods each have a one micron flux cartridge and have treatedthe product stream as shown in FIG. 8D. The TDS for both product andreject streams has increased to 10.6 and 10.7 ppt, respectively. Theconductivity likewise has increased to 21.2 and 21.2 mS, respectively.The specific gravity for both product and reject streams has increasedto 1.006 and 1.006, respectively. The chlorides have further decreasedto 8,307 and 7,987, respectively. The pH for both product and rejectstreams has decreased from the value measured from the start sample to8.47 and 8.39, respectively. After four stages, the product streamturbidity has dropped to 2 NTU while the reject stream turbidity hasbeen further concentrated to 33 NTU.

The changes in these properties from beginning to end of the processindicate that the product stream has been purified from contaminants andthe reject stream has been enriched with contaminants. Further, thechemical makeup of the contaminants in both streams has been changed asindicated by the change in values of TDS, pH, conductivity, specificgravity, and chlorides present.

In a further embodiment, the filter membrane or flux cartridge cancomprise a catalyst (e.g. cobalt-molybdenum, alumina, aluminosilicatezeolite, palladium, platinum, nickel, rhodium) to decontaminate some ofthe impurities in produced water. Such catalyst should be selected so asto target a particular chemical compound or element, or set of chemicalspecies.

In another embodiment, a heated or non-heated gaseous stream can be usedto aerate the produced water or any of the streams in the process. Suchaeration may occur before any filtration, at any stage of filtration, orbetween stages of filtration. Such additional gaseous stream furtheraids in filtration and separation of contaminants from the water. Oxygenor other gaseous species chemically reacts with the contaminants furtherimproving the quality of the treated aqueous product. For example, aheated air, oxygen stream, or hydrogen stream can be added at any stageto the aqueous stream being treated. The examples of heated andnon-heated gases are provided for purposes of illustration and notlimitation.

The instant invention results in numerous advantages. First, it providesan efficient method for cleaning or filtering produced water to thepoint where it may be potable or may be further treated to becomepotable. Such invention reduces the cost of treating contaminated waterand/or generating cleaner, usable water. Second, the invention providesa way to clean produced water such that the effluent complies withenvironmental standards. Such cleansed water may be safely released tothe surface or re-injected back into the ground, and the contaminantsmay be further concentrated and can then be more appropriately disposedof or used. Third, the invention can help to provide a more stable feedstock to other processes requiring a cleaner low-cost aqueous stream.Fourth, the invention can be portable and skid-mounted and can be placednear a well head and filter water wherever needed. Pumping costs arethereby reduced as contaminants are removed closer to the source ofcontamination. Fifth, it provides for a more economical overallfiltration operation.

Having thus described several aspects of at least one embodiment of thisinvention, it is to be appreciated that various alterations,modifications, and improvements will readily occur to those skilled inthe art. Such alterations, modifications, and improvements are intendedto be part of this disclosure, and are intended to be within the spiritand scope of the invention. Accordingly, the foregoing description anddrawings are by way of example only. While the invention has beenparticularly shown and described with reference to a preferredembodiment, it will be understood by those skilled in the art thatvarious changes in form and detail may be made therein without departingfrom the spirit and scope of the invention.

I claim:
 1. A separator apparatus for treating wastewater, comprising:at least one separator with at least one annulus disposed therein; aflux cartridge with a semi-permeable membrane seated inside saidannulus, wherein a fluid ring exists between an interior surface of theannulus and an exterior surface of the flux cartridge; a first pump influid communication with the separator capable of delivering an influentfluid containing at least one contaminant into the separator, whereinthe rhythmic pressure delivered by the first pump causesturbulence-induced cavitation within the fluid ring of the separatorwhich results in the retention of contaminant particles on the exteriorsurface of the flux cartridge and the collection of the filtered fluidwithin an interior chamber of the flux cartridge wherein the first pumppumps contaminated fluid influent into the separator through twoalternating fluid paths, wherein the fluid influent is moved through thefirst path by the upward movement of a piston inside the first pump andis moved through the second fluid path by the downward movement of saidpiston; a second pump in fluid communication with the separator capableof reversing the flow of fluid through the flux cartridge, whereinfiltered fluid is pumped into the fluid ring from the interior chamberof the flux cartridge which provides for the removal of the contaminantparticles retained by the flux cartridge and transports a substantialportion of the contaminant particles out of the separator; a reject tankin fluid communication with the separator which receives a substantialportion of the contaminant particles from the separator; and a producttank which receives a substantial portion of the filtered fluid from theseparator.
 2. The apparatus according to claim 1, further comprising: atleast one concentrator in fluid communication with the separator,containing at least one concentrator annulus disposed therein; and, aconcentrator flux cartridge with a semi-permeable membrane seated insidethe concentrator annulus, wherein a fluid ring exists between theinterior surface of the annulus and the exterior surface of the fluxcartridge, wherein a substantial portion of the contaminant waste andfluid flushed from the separator enters the interior chamber of the fluxcartridge seated within the concentrator and wherein the contaminant ofa desired dimension is retained on the interior surface of theconcentrator flux cartridge and a substantial portion of the filteredfluid is collected in the fluid ring of the concentrator.
 3. Theapparatus according to claim 1 further comprising a plurality ofseparators which are operated in at least one of a series or parallelconfiguration.
 4. The apparatus according to claim 1, furthercomprising: a reverse osmosis membrane in fluid communication with theseparator.
 5. The apparatus according to claim 1 wherein at least oneflux cartridge is impregnated with a biocide.
 6. The apparatus accordingto claim 1 wherein at least one flux cartridge comprises anelectrochemical cell.
 7. The apparatus according to claim 1 wherein atleast one flux cartridge is subjected to a magnetic force upon entryinto the fluid ring of the separator.
 8. The apparatus according toclaim 1 wherein at least one flux cartridge is coupled with anultrasonic wave source.
 9. The apparatus of claim 1 further comprising:at least one transition plate in fluid communication with the separatorfor distributing the influent fluid stream into the separator.
 10. Theapparatus according to claim 1, further comprising: a slipstream fluidpath in fluid communication with the separator which acts to enhance theturbulent flow of contaminated influent within the separator therebyimproving the filtration efficiency of the separator.
 11. The apparatusaccording to claim 1 further comprising a control panel which includes aplurality of control inputs for monitoring and operating the molecularseparator apparatus by a user.
 12. The apparatus according to claim 1further comprising: a hydrocarbon removal unit in fluid communicationwith the separator.
 13. The apparatus according to claim 1 furthercomprising: a heat source in fluid communication with the separator. 14.The apparatus according to claim 1 further comprising: an ultravioletdisinfection source in fluid communication with the separator.
 15. Theapparatus according to claim 1 wherein at least one poppet valvecontrols the flow of fluid into the separator.
 16. The apparatusaccording to claim 1 wherein a plurality of poppet valves are cycledincrementally to control the flow of fluid through the separator. 17.The apparatus of claim 1 wherein the molecular separator is detachablysecured to a wheeled transport.
 18. The apparatus of claim 1 whereinsaid flux cartridge comprises a reusable filter.
 19. A separatorapparatus for treating wastewater, comprising: at least one separatorwith at least one annulus disposed therein; a flux cartridge with asemi-permeable membrane seated inside said annulus, wherein a fluid ringexists between an interior surface of the annulus and an exteriorsurface of the flux cartridge; a first pump in fluid communication withthe separator capable of delivering an influent fluid containing atleast one contaminant into the separator, wherein the rhythmic pressuredelivered by the first pump causes turbulence-induced cavitation withinthe fluid ring of the separator which results in the retention ofcontaminant particles on the exterior surface of the flux cartridge andthe collection of the filtered fluid within an interior chamber of theflux cartridge; a second pump in fluid communication with the separatorcapable of reversing the flow of fluid through the flux cartridge,wherein filtered fluid is pumped into the fluid ring from the interiorchamber of the flux cartridge which provides for the removal of thecontaminant particles retained by the flux cartridge and transports asubstantial portion of the contaminant particles out of the separatorwherein only one separator is in fluid communication with the secondpump and wherein the flow of fluid received from the second pump isalternated between a plurality of separators at regular intervals andthe treated fluid from the plurality of separators that are not in fluidcommunication with the second pump bypass the second pump and flowdirectly into a collection reservoir; a reject tank in fluidcommunication with the separator which receives a substantial portion ofthe contaminant particles from the separator; and a product tank whichreceives a substantial portion of the filtered fluid from the separator.